Cards, such as subscriber identity module (SIM) cards, smart cards and memory cards carry an integrated circuit (IC). These cards are installed or otherwise inserted into mobile communication devices (e.g. cellular telephones) which contain subscriber related data. For example, these cards are used in those cellular telephones that conform to the global system for mobile communications (GSM) standard, the third generation code division multiple access (CDMA) standard, or other products, and may include many personal communication services (PCS) applications. GSM cellular telephones, or other SIM based devices are typically not fully functional without the SIM cards being inserted. Each SIM card contains a body, an IC that houses a processor and a memory, the memory storing algorithms, and the processor operational to encrypt voice and data transmissions. The memory also contains data that identifies the caller as being a legitimate user of the mobile network.
Conventionally, SIM cards are maintained within a cellular telephone in a card holder. However, with the increasing amount of features and capabilities provided by cellular telephones, multiple cards are oftentimes required to provide appropriate functionality and user flexibility. Conventional multiple SIM card design employ a housing structure where the plurality of SIM cards are placed next to each other (e.g. side-by-side) on the circuit board of the cellular telephone. This has the effect of substantially reducing the amount of available area for other circuits; thereby, potentially having an adverse effect on the overall functionality that may be provided by the cellular telephone. In addition, employing multiple SIM cards increases the overall size of the cellular telephone. With the ever increasing importance of scaling down, or reducing, the size of cellular telephones, side-by-side placement of the SIM cards impedes any size reduction efforts.